I bought this on VHS several years ago. The evolution clip was cut for time constraints, which is sad because even in its rough form you can see that it would have been one of the best pieces in the movie.
I never saw Heavy Metal 2000 because from the description it didn't seem to have anything to do with the original, except that it's animated and has lots of heavy metal on the soundtrack. I did buy the soundtrack, though, because the band Zilch had a song on it, and I was heavily into hide and X Japan at the time. The rest of the soundtrack was junk, though, and I think I ended up throwing it away. I still have the original movie's soundtrack and score around here somewhere, though.